In conventional magnetic drug delivery, magnetically-responsive objects coated by or containing therapeutic agents are injected systemically and are then focused to targets in the body by applied magnetic fields. This can become useful for treatment of cancer, stroke, infection and other diseases because it allows therapy to be concentrated to disease sites (solid tumors, blood clots, infections) while keeping systemic concentrations low (thus minimizing side effects). The magnetically-responsive objects can be micro- or nano-scale iron oxide or other particles coated appropriately to be bio-compatible and therapeutically effective. Sub-micron particles are small enough to pass from the blood to the surrounding tissue through blood vessel walls. Other objects besides particles, such as polymer, microsphere, micelle, and nano-capsule delivery systems, can also be made magnetic or attached to magnetic particles and then used as magnetic carriers.
There is always a need for improved devices, systems, and methods for magnetic agent delivery. It is to this need, among others, that this disclosure is directed.